MIGDAS-2 vs ADOS-2: How Autism Assessment Tools Differ

If your child is being assessed for autism, you may come across the names of different assessment tools. Two that are often mentioned are the MIGDAS-2 and the ADOS-2. This article explains, in plain language, what each one is and how they differ. Neither is presented as better than the other, because the right choice depends on the individual child.

What is the MIGDAS-2?

MIGDAS-2 stands for the Monteiro Interview Guidelines for Diagnosing the Autism Spectrum, second edition. It is a conversational, sensory and interest based framework. Rather than a fixed set of tasks, it guides the clinician through a flexible conversation shaped by the things your child is interested in and how they experience the world through their senses. It gathers information from the child, from parents or carers, and, where relevant, from educators.

What is the ADOS-2?

ADOS-2 stands for the Autism Diagnostic Observation Schedule, second edition. It is a semi structured, standardised observational assessment. It uses a set of planned activities designed to create opportunities for the clinician to observe communication, social interaction and play. The clinician records and scores what they observe against defined criteria.

How they differ

The main difference is in their style. MIGDAS-2 is flexible and conversation led, and follows the child's interests. ADOS-2 is more structured and standardised, with set activities and coded scores. Because MIGDAS-2 is built around a child's own interests and sensory preferences, some children find it calmer, particularly those who mask their difficulties or present atypically in unfamiliar, structured settings. ADOS-2, on the other hand, provides a highly standardised observation.

How clinicians choose

An autism assessment is never based on a single tool alone. Clinicians consider the whole picture, including developmental history, information from home and school, and standardised measures. They select the tool, or combination of tools, that best suits the individual child and the questions being asked. At Hunter Children's Clinics, the psychology team uses the MIGDAS-2 where possible, with the ADOS-2 and the Autism Diagnostic Interview, Revised (ADI-R) available where they are clinically indicated.

Which children might find MIGDAS-2 helpful

Because the MIGDAS-2 follows a child's interests and considers their sensory experiences, it can be a gentler experience for children who become anxious with unfamiliar, structured tasks. This includes some children who have learned to mask their difficulties, and children whose presentation does not fit the pattern that structured tests were originally designed around. That said, comfort is only one consideration. The clinician always weighs up what will give the most accurate and complete picture for a particular child.

What the tools have in common

Despite their differences, both tools share the same goal: to gather good quality information that, alongside history and other measures, helps a clinician reach a sound conclusion. Neither tool diagnoses autism on its own. A diagnosis is a clinical judgement that draws together many sources of information, and the assessment tool is one part of that wider process.

What this means for families

For parents, the practical message is reassuring. You do not need to choose the tool yourself, and you do not need to worry that one label on a form determines the outcome. The clinician makes that decision based on your child, and they can explain their reasoning to you. If you have questions about which approach will be used, it is completely reasonable to ask at the initial consultation. Understanding the process can help both you and your child feel more comfortable going in.

You can read more about our approach on our autism assessment page.

This article is general information only and is not a substitute for individual medical advice. If you have concerns about your child, please speak with your GP or paediatrician.